The present invention relates generally to vehicular lighting systems, and more particularly to lighting systems for illuminating the underlying and/or proximate surface for anticollision and other purposes.
The threat of collisions between aircraft is a particularly serious concern for the aviation industry. Air traffic control reduces the possibility of collisions by separating aircraft during flight and maintaining safe distances between aircraft that are landing and other aircraft, either in the air or on the ground. Additionally, the principle of xe2x80x9csee and be seenxe2x80x9d provides a means to decrease the chance of a collision between aircraft. Many see and be seen navigational aid devices and systems make use of light to identify and draw attention to the presence and location of aircraft. Conventional light sources use incandescent and halogen lamps and light emitting diodes for illumination purposes.
Conventional aircraft external lighting systems typically comprise navigation lights, anti-collision lights, landing and taxi lights, recognition lights, and ice detection lights. Navigation lights include a red light on the left wingtip, a green light on the right wingtip, and a white light(s) visible from the rear of the aircraft, with the white lights being on the wingtips and/or the tail. Anti-collision lights include strobe lights at the wingtips and sometimes the tail, and red rotating or flashing beacons on the fuselage, with the red rotating beacons used to indicate that engines are running. Landing and taxi lights are forward facing white lights designed to illuminate pavement, but with taxi lights also used to show the crew""s intention to taxi and landing lights used to indicate the crew""s belief that they are cleared for takeoff. These are also used to make the aircraft more visible to observers in front of the airplane in both day and night conditions. Recognition lights are small floodlights that illuminate the sides of the vertical stabilizer and rudder. Ice detection lights illuminate the leading edge of the wing(s) so that the flight crew can see at night if ice is accumulating.
While conventional aircraft lighting systems are helpful, there is a continuing need for improvements in aircraft lighting systems to prevent collisions between aircraft on the ground and ground vehicles, taxiing aircraft, aircraft that are landing and aircraft that are taking off. In this regard, taxi lights, recognition lights, and ambient light have not been completely successful in some situations in preventing collisions with aircraft on the ground. For example, vehicles and other aircraft approaching from the side or from behind an aircraft on the ground and, similarly, landing aircraft approaching from the side or rear may not become aware of the presence of an aircraft. In these situations, the warning provided by conventional aircraft light systems has sometimes proved ineffective. Taxi lights are often not visible except from in front of an aircraft. Recognition lights often do not provide sufficient illumination to attract enough attention to prevent collisions.
It would therefore be advantageous to further reduce the possibility of collisions with an aircraft on the ground by providing an improved means for detecting aircraft on the ground by ground vehicles, taxiing aircraft, aircraft that are landing and aircraft that are taking off.
A surface illumination system is therefore provided that includes a lighting system mounted upon a vehicle body, such as an aircraft body. The lighting system is adapted to illuminate the surface beneath and/or around the periphery of the aircraft. For example, the lighting system is preferably adapted to illuminate the surface beneath at least one of the tail and distal ends of the wings. A further embodiment of the lighting system is adapted to illuminate the surface in a non-static manner. Preferably, the illumination pattern should be obviously and significantly different from illumination from building lights, floodlights, headlights or other types of lights within or near an airport such that the illumination pattern is uniquely identifiable as that generated by an aircraft. By increasing the illumination about the periphery of the aircraft, the surface illumination system draws increased attention to the aircraft and provides ground vehicles, taxiing aircraft, aircraft that are landing and aircraft that are taking off with advanced warning of the presence and position of the aircraft on the ground, thereby reducing the possibility of collisions.
A vehicle, such as an aircraft, equipped with a surface illumination system typically includes a light system, comprised of a plurality of light sources, for illuminating the ground in proximity to the aircraft. Radiance may occur in a generally downward direction so as to provide illumination of the ground directly beneath and, more importantly, proximate to and extending beyond the periphery of the aircraft. Advantageously, the light system provides illumination about a majority of the periphery of the vehicle. For an aircraft, the lights are preferably positioned to provide illumination under and around the nose, wingtips, and tail of an aircraft. Extending the area of ground illumination beyond the periphery of the aircraft allows landing aircraft to better view the illumination that otherwise would be difficult to see if only the ground directly beneath the aircraft was illuminated, which illumination could be partially blocked by the aircraft itself.
A light positioned at the front of the aircraft is advantageous when the aircraft is holding short of the runway. A light positioned at the tail of the aircraft is advantageous when the aircraft is holding in position on the runway to provide notice to vehicles or aircraft approaching from the rear. Lights positioned on the wingtips are also particularly advantageous while the aircraft is taxiing to provide a warning to vehicles or aircraft approaching from the side. Although the position of each light has a particular importance, the entire series of lights may be lit to increase the overall visibility of the aircraft and to decrease the chance of collisions with an aircraft.
One advantageous aspect of the surface illumination system is the use of variant, non-static, emissions from the lights. In order to draw attention to the presence, position and orientation of the obstacle aircraft, the plurality of lights may provide illumination that varies over time in any combination of size, shape, color, position, frequency, and intensity. Additionally, the sequence of illumination and/or the pattern of illumination may be varied.
The light sources of the present invention may be of any type such as incandescent or halogen lamps or light emitting diodes. The selection of light source may depend upon the competing desires of providing sufficient ground illumination without ruining the night vision in the aircraft or others in nearby vehicles or aircraft. These competing desires may be balanced by directing the light, maintaining a low level of intensity, or any other method.
Although a low level of intensity is advantageous so as not to obstruct the view of the pilots in the aircraft or others nearby, the intensity of light produced by the surface illumination system of the present invention should be sufficient to provide warning to other vehicles and aircraft. The surface illumination system is preferably able to attract attention from ground vehicles and taxiing aircraft at a few hundred yards. A visible range of about a mile is suggested to attract the attention of landing aircraft when the illuminating aircraft is holding for takeoff on the runway; while half a mile is suggested when holding on an adjacent taxiway.
Therefore, the surface illumination system of the present may decrease the chance of collisions with aircraft on the ground by providing increased illumination in the vicinity of the aircraft which, in turn, notifies others of the presence of the aircraft. In particular, the illumination of the surface beneath and around the aircraft, as well as a non-static manner of illumination, provides landing and taxiing aircraft and ground vehicles advanced warning of the presence of the illuminating aircraft on the ground.